Stop mechanism.



R. C. SIMMONS. STOP MECHANISM. APPLICATION FILED 50, 18, 1911.

Patented Jan. 11, 1916.

COLUMBIA PLANoGRImn 60-. WASHxNuToN. B. c.

nnrrnn snares Arsnr opinion RALPH C. SIMMONS, 0F BEVERLY, DEASSAGHUSETTS, ASSIGNOR TO UNITED SHOE MACHINERY COMPANY, OF PATERSON, NEW JERSEY, A CORPORATION OF NEW JERSEY.

STOP MECHANISM.

Specification of Letters Patent.

Patented Jan. i1, 131%.

To all whom it may concern:

Be it known that I, RALPH G. SIMMONS, a citizen of the United States, residing at Beverly, in the county of Essex and State of Massachusetts, have invented certain new and useful Improvements in Stop Mechanisms; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to improvements in stop mechanisms.

The primary object of the present invention is to produce an improved stop mechanism which will act to stop the rotation of a shaft at a definite point in its rotary movement in a uniform and reliable manner without undue shock or vibration and without excess strain on the parts of the machine, even when the shaft is rotating at high speed. In certain machines, such as chain stitch shoe sewing machines, it is desirable, upon stopping the machine, first to arrest the forward rotation of the shaft, and thereafter to im art a reverse or return movement to the shaft to bring the shaft and the parts of the machine to stopping positions, and in the illus rated embodiment of the invention the stopping mechanism is particularly desi ned to secure these results. It is to be understood, however. that certain features of the invention are not limited to stop mechanisms which act to reverse the rotation of the shaft before it is finally brought to rest, but may be embodied in mechanisms which operate to arrest the rotation of the shaft without reversing it.

The features of the invention consist of certain novel combinations and improved constructions and ar an ement of parts hereinafter described and particularly pointed out in the claims, the advantages of which will be obvious to one skilled in the art. 7

In the drawing; illustrating the invention in its preferred form as applied to a welt and turn shoe sewing machine of a type well known in the art, Figure 1 is a side elevation of a portion of the machine illustrating cer tain parts of the stop mechanism in section; Fig 2 is a sectional view taken on the line 2-2 of Fig. 1 looking in the direction of the arrows.

The various parts of the shoe sewing machine to which the stop mechanism, as illustrated, is applied are driven by a main shaft 1 on which is mounted a pulley 2 in operative connection with a shaft 3. A driving shaft 4 is arranged in alinement with the shaft 3 and a friction clutch member 5 is mounted on shaft 4 to rotate therewith and arranged to slide longitudinally of the shaft into and out of engagement with a cooperating friction clutch member 6 secured to the shaft 3. The stop mechanism in the present embodiment of the invention is applied directly to the shaft 1 and is designed, upon the completion of the sewing of the work, to stop the rotation of said shaft, to impart a return movement thereto, and to bring the shaft to rest at a given and certain point in the cycle of operations without undue shock or jar. The said stop mechanism comprises in the construction illustrated a reciprocatory member or slide 7 arranged to be reciprocated by suitable mechanism connecting the said member with the shaft 1 and a second reciprocatory member or slide 8 arranged to reciprocate normally with the slide 7. The slide 8 is hollow and the slide 7 is slidably mounted therein. The outward movement of the slide 7 with relation to the slide 8 is limited by the head 9 of a rod 10 arranged to slide freely through the head 11 of the slide 8 and secured at its inner extremity to the slide 7. A heavy coil spring 12 surrounding the rod 10 is interposed between the slide 7 and the head of the slide 8 and operates to maintain the slide 7 normally at the outer end of the slide 8 as illustrated in Fig. l. The slide 8 is arranged to reciprocate in a guide 13 in the frame of the machine. The connecting mechanism for reciprocating the slide 7 from the shaft 1 comprises a link 14 connected at one extremity with the slide 7 and at the other by means of a pin 15 with an eccentric rod 16 having an eccentric strap 17 embracing an eccentric 18 secured to the shaft 1. The link l t and the eccentric rod 16 are pivotally connected by the pin 15 with one arm of a walking beam 19 arranged to oscillate on a shaft 20. During the normal rotation of the shaft 1 the slide 7 is reciprocated b the mechanism connecting the sa d slide with the shaft and the slide 8 normally reciprocates with the slide 7 in the guide 13, the slides 7 and 8 being maintained in the the valve rod, is interposed between the rod and an adjustable screw 31, secured in the bore 28 to yieldingly urge the valve rod to the right, Fig. 1. When the shaft 1 is in normal operation the valve rod 27 is located. in a position to the left of the position in which it is shown in Fig. 1 so that the groove 29 is in registration with the port 24. When the valve rod is in this position air is permitted to enter the cylinder freely and to exhaust freely therefrom during the outward and inward movements of the piston 22 in the cylinder. When the valve rod is in the position illustrated in Fig. 1 port 24: is closed thereby and during the outward movement of the piston 22 air is permitted to enter freely through the port 25 but during the inward movement of the piston in relative postions illustrated in Fig. 1 by the rod 10 and coil spring 12. When the stop mechanism is thrown into operation the re ciprocatory movement of the slide 8 is arrested at the beginning of its downward or ou-tward stroke by mechanism to be hereinafter described and the further rotation of the shaft 1 operates through the connecting mechanism to carry the slide 7 downwardly within the slide 8, compressing coil spring 12 between the slide 7 and the head 11 of the slide 8. The resistance of the spring to the movement of the slide 7 acts through the mechanism connecting said slide with the shaft to retard or check the forward rotary movement of said shaft, and when the reactive force of the spring is sufficient to overcome the inertia of the machine, the forward rotation of the shaft is arrested. the cylinder the valve at the port 25 prevents Coil spring 12 is preferably constructed of the escape of air at said port. Since the air suflicient strength to stop the forward move-litwithin said cylinder can then escape only ment of the shaft in less than half a. revolultfthrough the check valve 26 which is contion thereof after the stop mechanism is '1? structed to permit the air to escape slowly thrown into operation. During the down- :lfrom the cylinder, the downward movement ward or outward movement of the slide 7 *of the piston 15 is retarded.

within the slide 8 the coil spring 12 is considerably compressed and when the forward rotation of the shaft 1 is arrested the recoil or reactive force of the spring imparts a reverse rotation to the shaft 1 through the slide 7 and the mechanism connectin the said slide with the shaft.

In order to retard the reverse or return movement of the shaft 1 and the mechanism connected therewith due to the rebound or recoil of the coil spring 12 so that the shaft may be brought to rest without undue shock or jar, pneumatically controlled mechanism is provided to check or retard the re turn movement of said shaft. This pneumatically controlled mechanism comprises in the illustrated embodiment of the invention a dashpot consisting of a cylinder 21 in which operates a piston 22 connected by means of a link 23 with the other arm of the walking beam 19. The cylinder 21 is provided with a normally open intake and exhaust port 2% and with a port 25 controlled by a valve permitting the free entrance of air therethrough into the cylinder but preventing the exhaust of air from the cylinder through said port. A check valve 26 is mounted in a bore leading to the interior of the cylinder and is constructed to permit the slow escape of air from the cylinder therethrcugh. A valve rod 27 is mounted in a guide bore 28 in the head of the cylinder intersecting the intake and exhaust port 24:. The said valve rod is provided with a groove 29 forming a by-pass about which the air is permitted to flow in entering the cylinder and in escaping therefrom when the valve rod is operated to bring the groove into registration with the intake and exhaust port 24. A coil spring 30, seated in the head of hand extremity, Fig. 1 with a catch 32 which is arranged to engage a shoulder 33 on the slide 8 when the valve rod is moved to its fiextreme right hand position to close the lport 24, thereby arresting the reciprocatory movement of said slide. The shoulder 33 is formed on the slide 8 at a point such that the catch 32 engages said shoulder when the slide 8 is at the turning point in its reciprocatory movement. is moved to the left from the position shown in Fig. l the catch 32 is released from the shoulder 33 from the slide 8 thereby permitting the said slide to reciprocate freely within the guide 13 and the roove 29 is brought into registration with the port 2i, thereby hau st fronrthe cylinder 21. This is the position which the rod is caused to assume When it is desired to stop the machine at once, the valve rod is urged to the right and when the slide 8 reaches the upper limit of its stroke, the valve rod is moved into the position shown in Fig. 1 bringing the catch 32 in position to engage the shoulder on the slide 8, thereby arresting the downward or outward movement of said slide in the guide 13. By this movement of the valve ward rotation of the shaft 1 due to the momentum of the machine carries the slide 7 downwardly within the slide 8, therebv compressing the heavy coil spring 12 between the head of the slide 8 and the slide 7. At the same time the piston 22 is moved outwardly within the cylinder 21, air being permitted to enter freely into said cylinder through the port 25. The resistance of the The valve rod 27 is provided at its right.

lVhen the valve rod.

permitting the air to freely enter and ex-.

when the machine is in normal operation.

rod the port 24 is closed. The further forspring 12 to the inward movement of the slide 7 acts through the connecting mechanism between said slide and the shaft 1 to check the movement of said shaft and when the resistance or reaction of the spring is sufficient to overcome the inertia of the machine, the forward movement of the shaft is arrested. Immediately thereafter the re bound or recoil of the spring causes the slide 7 to move outwardly within the slide 8 and thereby imparts a reverse rotation to the driving shaft 1. At the same time piston is moved inwardly Within the cylinder 21.

Since the valve at the port 25 immediately closes and prevents the escape of air there through as the piston 22 tends to move inwardly within the cylinder, the inward movement of the piston is immediately checked or retarded and the reverse rotation of the shaft 1 is also checked. The check valve 26 permits the air to escape slowly from the cylinder and the piston moves slowly toward the inner end of the cylinder under the influence of the coil spring 12. A steady gradual return movement is imparted to the main shaft 1 and when the slide 7 and the piston 22 reach the limits of their strokes the shaft is brought to rest-in the position illus trated in Fig. 1 without jar or shock.

The valve rod 27 is controlled in the con.- struction illustrated by mechanism comprising a vertical rod 34 arranged to slide in a guide bore 35 in a frame and formed with a slot 36 through which the valve rod passes. The valve rod is provided with diametrically arranged pins 37 on opposite sides thereof which project into cam slots 38 in the rod 34. The rod 34 is yieldingly urged upwardly by means of a coil spring 38 surrounding the same and hearing at its eX- tremities against a head 39 attached to the rod and a shoulder 40 on the frame respectively. The rod 34 is moved downwardly within the guide bore 35 by means of a treadle 41 connected. with said rod by means of a rod 42, passing loosely through a bore 43 in a lug 44 secured to said rod, the downward movement of the rod 42 in the bore in said lug being limited by a nut 45. A spring member 52 is attached at one extremity to the treadle and at the other to a stationary part of the frame to lift the treadle when it is released.- The treadle is secured to a suitable shaft 46 and upon this shaft is mounted an arm 47 arranged to engage and operate the clutch member 5 to bring the said clutch member into and out of engagement with the cooperating clutch member 6. The position which the treadle assumes when the machine is normally operatin is indic ted at A in dot and dash lines in Fig. 1. hen the treadle is in this position the clutch member 5 is held in engagement with the clutch member 6 and the rod 34 is held in lowermost position with the pins 37 oc-.

cupying the upper ends of the slots 38. When it is desired to stop the machine without throwing the stop mechanism into operation so that the main shaft 1 may be turned freely by the operator, the treadle is released and allowed to rise to the position indicated at B in dot and dash lines in Fig. 1. By this movement of the treadle the clutch member 5 is released from engagement with the clutch member 6 and the rod 34 rises under the influence of the spring 38. The shape of the cam slots 38 is such that during this partial upward movement of the rod 34, the valve rod 27 is held in its left hand position maintaining the groove 29 in registration with the exhaust port 24 and the catch 32 out of engagement with the Shoulder 33 on the cylinder 8 so that the machine is allowed to slow down gradually and come to a stop. In order to hold the rod 34 in this intermediate position the said rod is provided with a recess forming a shoulder 48 which engages a projection 49 upon a lever 50 which is held in position for engagement with said shoulder by a weight 51 attached to said lever. When the treadle is allowed to rise to the position indicated at B, the rod 34 rises until the shoulder 48 engages the projection 49 on the lever 50 and the rod is held in this intermediate position by said lever.

l/Vhen it is desired to stop the machine at once, the treadle is completely released and rises under the influence of the spring 52 to the position indicated in full lines in Fig. 1. During this movement of the treadle the rod 34 rises as before until the shoulder 48 engages the projection 49 on the lever 50 and thereafter the rod 42 moves upwardly through the bore in the lug 44 until it engages the lever 50. The said rod lifts the lever 50 to substantially the position illustrated in Fig. 2 thereby moving the projection 49 out of engagement with shoulder 48, permitting the rod 34 to rise farther under the influence of the spring 38. The shape of the cam slots 38 is such that during this latter half of the upward movement of the rod 34, the valve rod 27 is moved to the right, Fig. 1 until the catch end of said rod impinges against the face of the slide 8. lVhen the slide 8 reaches the upper end of its stroke, the rod 34 rises still farther-under the influence of the spring 38 and the valve rod 27 moves to the posi tionillustrated in Fig. 1, thereby throwing the stop mechanism into operation.

It is to be noted that the stop mechanism is thrown into operation always at the same point in a rotation. of the main shaft 1. The shaft is always brought to rest with slide 7 at the outer end of the slide 8 and with the eccentric rod 16 and eccentric 18 at the o ter limits of their strokes as illustrated in Fig. 1. The stop mechanism therefore acts in a certain and uniform manner to bring the machine to rest at a given and certain point in a cycle of operations.

Although the invention is illustrated as .5 applied to a shoe sewing machine, it will be understood that it is applicable to machines for performing other operations, and the invention is not in general limited to the details of construction and arrangement of the illustrated embodiment but may be embodied in other forms without departing from the broader features of the invention.

Having explained the nature and object of the invention, and having specifically described a mechanism embodying the same in its preferred form, what is claimed is l. A stop mechanism having, in combination, a shaft, mechanism for arresting the go forward rotation of said shaft and for imparting a return movement thereto and a pneumatically controlled dash-pot acting through a material interval during the return movement of said shaft to retard the return movement of the shaft and cooperating with said mechanism to cause the shaft to rotate at slow speed to stopping position.

2. A stop mechanism having, in combination, a shaft, mechanism for arresting the forward rotation of said shaft and for imparting a return movement thereto and a dashpot connected with the shaft and acting through a material interval during the return movement of said shaft to retard the I return movement of the shaft and cooperating with said mechanism to cause the shaft to rotate at slow speed to stopping position.

3. A stop mechanism having, in combination, a shaft, mechanism acting to arrest the r forward rotation of said shaft, to impart a reverse rotation thereto and finally to bring the shaft to rest at a constant position, and a pneumatically controlled dash-pot acting through a material interval during the reverse rotation of said shaft to retard the reverse rotation of the shaft and cooperating with said mechanism to cause the shaft to rotate at slow speed to stopping position.

4:. A stop mechanism having, in combination, a shaft, mechanism to arrest the forward rotation of said shaft and to impart a return movement thereto comprising a spring arranged to be placed under progressively increasing tension bv the further forward rotation of the shaft after the stop 5. A stop mechanism having, in combination, a shaft, mechanism to arrest the forward rotation of the shaft and to impart a reverse rotation thereto comprising a spring arranged to be placed under progressively increasing tension by the forward rotation of the shaft afterthe stop mechanism is thrown into operation and acting to impart by its recoil a reverse movement to the shaft and a dashpot connected with the shaft and acting through a material interval during the reverse rotation of the shaft to retard actuating the piston from the shaft, and

means to throw the said inactive means into operation.

7; A stop mechanism having, in combination, a shaft, means for controlling the movement of the shaft comprising a cylinder having provision normally permitting the free entrance and exhaust of air, valve mechanism arranged to permit the free entrance of air into the cylinder but to retard the exhaust of air therefrom, a piston operating in the cylinder, a connection for actuating the piston from the shaft and means to throw the valve mechanism into operation.

8. A stop mechanism having, in cnmbination, a shaft, mechanism for controlling the movement of the shaft comprising a cvlinder having a normally open port for the entrance and exhaust of air, a valve rod arranged to close said port, valve mechanism arranged to permit the free entrance of air into the cvlinder but to retard the exhaust of air therefrom, a piston operating in the cvlinder, a connection between the piston and the shaft for actuating the piston from the shaft and means to operate the valve rod to close the said port.

9. A stop mechanism havingin combination, a shaft, a reciprocatorv member. connecting mechanism for operating said member from the shaft, a second member arranged to reciprocate normallv with the first member, a spring interposed between the members and means to arrest the reciprocatory movement of the second member.

10. A stop mechanism having. in combination, a shaft, a slide. connecting mechanism for operating the slide from the shaft,

a second slide arranged to reciprocate normally with the first slide, a compression spring interposed between the slides and means under the control of the operator for arresting the reciprocatory movement of the second slide.

11. A stop mechanism having, in combination, a shaft, a slide and connecting mechanism for reciprocating the slide from the shaft, a second slide arranged normally to reciprocate with said first slide, a spring interposed between said slides, a walking beam operated by said connecting mechanism, a cylinder having a normally open main intake and exhaust port, valve mechanism arranged to permit the free entrance of air into said cylinder but to check the exhaust of air therefrom, a piston connected with said walking beam andoperating in said cylinder and means to arrest the reciprocating movement of the second slide and to closethe main exhaust port simultaneously.

12. A stop mechanism having, in combination, a shaft, a slide and connecting mechanism for reciprocating said slide from the shaft, a second slide arranged normally to reciprocate with the first slide, a spring member interposed between said slides, a walking beam operated through said connecting mechanism, a cylinder having a normally open main intake and exhaust port, valve mechanism arranged to permit the free entrance of air into said cylinder but to check the axhaust of air therefrom, a piston actuated by the walking beam and operating in said cylinder, a valve rod arranged to close said port and having means for arresting the reciprocating movement of the second slide, mechanism under the control of the operator for actuating said valve rod to close the said port and arrest the reciprocation of the second slide simultaneously.

13. A stop mechanism having, in combination, a shaft, mechanism acting to retard the forward rotation of said shaft and thereafter to rotate the shaft to stopping position, pneumatically controlled mechanism for retarding the rotation of the shaft imparted by said mechanism comprising a cylinder having a normally open main intake and exhaust port, valve mechanism arranged to permit the free entrance of air into said cylinder but to check the exhaust of air therefrom, a valve rod arranged to close said port and having means to throw said first mechanism into operation, a rod for controlling said valve rod having a cam slot formed therein, a pin secured to said valve rod and operating in said cam slot, mechanism under the control of the operator for operating said last rod to thereby actuate the valve rod to close and open the said port and to throw said first mechanism into and out of operation.

14. A stop mechanism having. in combination, a shaft, a reciprocatory member, connecting mechanism for operating said member'from the shaft, a second member an ranged to reciprocate normally with the first member, a compression spring interposed between the members and means to arrest the movement of the second member at the turning point in its reciprocatorymovement.

15. A stop mechanism, having, in combination, rebound mechanism acting to slow down the rotation of the shaft and thereafter by its recoil to rotate the shaft through a substantial part ofa revolution to stopping position, a daslrpot acting to retard the rotation of the shaft imparted bythe rebound mechanism, and cooperating with said mechanism to cause the shaft to rotate at slow speed to stopping position.

16. A stop mechanism having, in combination, a shaft, a walking beam and con necting mechanism for. operating the walking beam from the shaft, a reciprocatory member connected with one arm of the walking beam, a second reciprocatory member connected with the other arm of said walking beam and means to cause the movement of one of said members to be yieldingly arrested and a return movement to be imparted thereto.

17. A stop mechanism having, in combination, a shaft, driving mechanism for the shaft, atl'eadle arranged to throw the driving mechanism into and out of driving connection with the shaft, mechanism for arresting the rotation of the shaft, a reciprocatory rod arranged while moving in one direction to throw the arresting mechanism into operation and while moving in the opposite direction to throw the said mechanism out of operation, a member connecting said rod with the treadle, a catch for preventing the movement of said rod to throw the arrest-ing mechanism into operation upon the partial. release of the treadle to throw the driving mechanism out of driving connection with the shaft, said member being arranged to throw out the catch upon the complete release of the treadle.

18. A stop mechanism, having, in combination, a shaft, a reciprocatorymember, connecting mechanism for operating said member from the shaft, a second member arranged to reciprocate normallv with the first member and having a resilient connection with the first member, and means for stopping the reciprocation of the second member to render the resilient connection eiieet've to retard the rotation of the shaft and by its recoil to rotate the shaft to stopping position.

19. A- stop mechanism, having, in combination, a shaft, a reciprocatorv member, connecting mechanism for operating said member from the shaft, a second member arranged to reciprocate normally with the first member and having a resilient connection with the first member, means for stopping the reciprocation of the second member to render the resilient connection elfective to retard the rotation of the shaft and by its recoil to rotate the shaft to stopping position, and means for controlling the recoil to cause the shaft to rotate at SlOW speed to stopping position.

20. A stop mechanism, having, in combination, a shaft, a member normally reciprocated by the shaft, a resilient connection between said member and the shaft, and means for stopping the reciprocation of said member to render the resilient connection effective to retard the rotation of the shaft and by its recoil to rotate the shaft to starting position.

21. A stop-mechanism having, in combination, a shaft, a reciprocating device reciprocated by the shaft, a treadle, means controlled by the treadle for stopping the reciprocation of said device, and a resilient connection acting upon stopping the reciprocation of said device to resist the rotation of the shaft, and by its recoil to move the shaft to stopping position. 7

22. A stop-mechanism having, in combination, a shaft, a reciprocating device reciprocated by the shaft, a treadle, means controlled by the treadle for stopping the reciprocation of said device, a resilient connection acting upon stopping the reciprocation of said device to resist the rotation of the shaft, and by its recoil to move the shaft to stopping position, and means for controlling the recoil of said device to cause the rotation of the shaft produced thereby to take place at approximately a uniform speed. 7 I

RALPH C. SIMMONS. 'l/Vitnesses: i

CHAUNCEY M. SINCERBEAUX, WARREN G. OGDEN.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents. Washington, D. C. 

